In California, permits to carry a concealed weapon are public record and available, according to The Huffington Post. The youngest son of Rick Warren had never applied for a CCW license through the department, the OCSD told the Post.

A source close to the investigation claimed that Warren used a shotgun, according to The Los Angeles Times, but the Sheriff’s Department declined to comment.

Rick Warren, evangelical leader and pastor of Saddleback Church in Lake Forest, Calif., announced his son's tragic death last Saturday.

"Today after a fun evening together with Kay and me, in a momentary wave of despair at his home, he took his own life," the author of "The Purpose Driven Life" said in a statement.

While Matthew was a kind, gentle and compassionate man, said Warren, he also revealed that his youngest son suffered from depression and suicidal thoughts.

"Only those closest knew that he struggled from birth with mental illness, dark holes of depression, and even suicidal thoughts," Warren wrote.

“In spite of America’s best doctors, meds, counselors, and prayers for healing, the torture of mental illness never subsided."

"I'll never forget how, many years ago, after another approach had failed to give relief, Matthew said 'Dad, I know I'm going to heaven. Why can't I just die and end this pain?'"

An autopsy confirmed Monday that Matthew Warren died of suicide through a self-inflicted gun shot wound, according to the Orange County coroner.